An engine fuel supply system associated with a gas pipeline compressor engine may include a hydrocarbon separation system. The hydrocarbon separation system may include a raw gas conduit fluidly connecting a raw gas supply to a separator, and a purified gas conduit fluidly connecting the separator to the gas pipeline compressor engine. The separator may be configured to isolate methane of the raw gas supply from higher carbon chainlength hydrocarbon molecules such as ethane, propane, butane, and the like, and in doing so, providing the gas pipeline compressor engine with a source of fuel for operation.
One hydrocarbon separation system design is described by Exterran (www.exterran.com) and is known as the JT System. As seen there, this publication describes a hydrocarbon separation system including a gas/gas exchanger and chiller for precooling a raw gas stream, a methanol injection system to prevent the formation of hydrates, a Joule-Thomson valve for expanding and cryogenically cooling the raw gas stream, and a separation drum for isolating gaseous methane from the higher carbon chainlength hydrocarbon molecules of the raw gas supply.
Importantly, the Exterran separation system describes the use of a gas/gas exchanger and chiller for precooling a raw gas stream and a Joule-Thomson valve for expanding and further cooling the raw gas stream to cryogenic temperatures, thereby necessitating the use of a methanol injection system to prevent the formation of hydrates in the purified gas stream. Accordingly, a need exists to provide a hydrocarbon separation system for a gas pipeline compressor engine that isolates methane and/or ethane from propane, butane, isobutane and pentane and isopentane, and other higher carbon chainlength hydrocarbon molecules, without needing to cool the raw gas supply to cryogenic temperatures.
The present disclosure is directed to overcoming one or more problems set forth above and/or other problems associated with the prior art.